OBJECTIVETo explore the effect of combination of pulsed CO2 laser irradiation and diammine silver fluoride treatment on the ultrastructure of dentine.

METHODSEach extracted molars was made into four identical dentinal specimens, which were randomly divided into 4 groups according to the treatment methods: A, control group; B, pulsed CO2 laser irradiation; C, coated with 38%Ag(NH3)2F; and D, laser irradiation plus fluoride. Scanning electron microscope (SEM) analysis was performed.

RESULTSAs shown by SEM, group A showed clear dentinal tubuli, group B showed melted surface without dentinal tubule openings, group C showed thicker melted layer without dentinal tubule openings, and group D showed the thickest melted and recrystallized layer on dentine surface.

CONCLUSIONSBoth pulsed CO2 laser irradiation and 38%Ag(NH3)2F treatment can seal dentinal tubule. The combination of these two techniques can form a synergistic effect.

Dentin ; drug effects ; radiation effects ; ultrastructure ; Fluorides ; pharmacology ; Humans ; Lasers ; Lasers, Gas ; Silver Compounds ; pharmacology

This article introduces antibacterial principle and antibacterial properties of silver nanoparticles, and makes a synthetical study of the bio-safety on nano-silver dressing, nano-silver gel, nano-silver anti-bacterial powder and silver nanoparticles.
Anti-Bacterial Agents ; Biocompatible Materials ; Equipment Safety ; Materials Testing ; Nanoparticles ; Silver Compounds

BACKGROUND: It is well-known that silver ions and silver compounds are broad-spectrum antimicrobial agents effective against gram-positive and gram-negative bacteria, and yeasts. Thus, silver ions, as an antibacterial agent, have been used in the components of materials used in medical devices or coatings. Recently, advances in nanotechnology have enabled manufacturers to develop silver particles of a nanometer size with a safer and more effective antimicrobial activity. So, we evaluate the antimicrobial activity of nanoSilver-coated gauze against clinical isolates. METHODS: Three kinds of nanoSilver-coated gauzes (100A, 800A, and 1,500A) were tested for antimicrobial activity by the disk diffusion method. The organisms tested included clinical isolates of nonfermentative gram-negative bacilli (143 isolates), aerobic gramnegative bacteria (188), aerobic gram-positive bacteria (397), anaerobic bacteria (46), and yeasts (161), and three reference ATCC strains. RESULTS: The susceptible rates to NanoSilver of nonfermentative gram-negative bacilli (NFB), aerobic gramnegative bacteria and aerobic gram-positive bacteria were 87%, 87% and 78%, respectively. Antimicrobial activity of NanoSilver against imipenem-resistant NFB, extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae, and methicillin-resistant Staphylcoccus aureus (MRSA) was similar to that against imipenem-sensitive NFB, ESBL non-producing Enterobacteriaceae, and methicillin-susceptible S. aureus. CONCLUSION: NanoSilver-coated gauze exhibits broad spectrum antimicrobial activities to a large number of gram-negative and gram-positive bacteria including imipenem-resistant NFB, ESBL producing Enterobacteriaceae, and MRSA.
Anti-Infective Agents ; Bacteria ; Bacteria, Anaerobic ; beta-Lactamases ; Diffusion ; Enterobacteriaceae ; Gram-Negative Bacteria ; Gram-Positive Bacteria ; Ions ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Nanotechnology ; Silver ; Silver Compounds ; Yeasts

PURPOSE: We want to validate the use of the silver-enhanced in situ hybridization (SISH) technique as comparised with fluorescence in situ hybridization (FISH) technique for assessing the HER2 gene amplification of breast carcinoma. METHODS: Tissue microarray (TMA) blocks from 58 breast cancer specimens were prepared and the concordance between HER2 gene amplification in breast cancer was determined by the FISH (PathVysion(R), Abbott/Vysis) technique and the automated silver in situ hybridization (SISH, INFORMtrade mark, Ventana) technique. For comparison, all the specimens were stained by immunohistochemistry (Ventana-PATHWAY(R)4B5). Evaluation was performed by two pathologists and with following the instructions of the manufacturers and the guidelines of the American Society of Clinical Oncology/College of American Pathologists. RESULTS: The results of SISH and FISH were identical in all 58 cases; 17 cases showed HER2 amplification, and on the other hand, 41 cases didn't show HER2 amplification. Five weakly positive (2+) cases in immunohistochemistry staining revealed one HER2 amplification and four no HER2 amplification on both SISH and FISH. The SISH results of the HER2/CEP17 ratio were well correlated with the FISH results of the HER2/CEP17 ratio (correlation coefficient r=0.745, Linear regression r2=0.555, p<0.001). CONCLUSION: The results of the SISH technique for assessing the HER2 status of excised breast carcinoma is comparable to the result obtained by FISH. However, SISH has the advantage of having permanent end result that can be visualized by an ordinary light microscope and less laborious preparation and time is needed than is required by FISH. SISH seems to be more feasible than FISH for assessing HER2 amplification of breast cancer.
Breast ; Breast Neoplasms ; Fluorescence ; Genes, erbB-2 ; Hand ; Imidazoles ; Immunohistochemistry ; In Situ Hybridization ; Light ; Linear Models ; Nitro Compounds ; Silver

We prepared silver nanoparticles/polyethyleneimine-reduction graphene oxide (AgNP/rGO-PEI) composite materials, and evaluated their quality performance in our center. Firstly, we prepared AgNP/rGO-PEI, and then analysed its stability, antibacterial activity, and cellular toxicity by comparing the AgNP/rGO-PEI with the silver nanoparticles (PVP/AgNP) modified by polyvinylpyrrolidone. We found in the study that silver nanoparticles (AgNP) distributed relatively uniformly in AgNP/rGO-PEI surface, silver nanoparticles mass fraction was 4.5%, and particle size was 6-13 nm. In dark or in low illumination light intensity of 3 000 lx meter environment (lux) for 10 days, PVP/AgNP aggregation was more obvious, but the AgNP/rGO-PEI had good dispersibility and its aggregation was not obvious; AgNP/rGO-PEI had a more excellent antibacterial activity, biological compatibility and relatively low biological toxicity. It was concluded that AgNP/rGO-PEI composite materials had reliable quality and good performance, and would have broad application prospects in the future.
Anti-Bacterial Agents ; chemistry ; Graphite ; chemistry ; Light ; Nanoparticles ; chemistry ; Oxides ; chemistry ; Particle Size ; Polyethyleneimine ; chemistry ; Silver Compounds ; chemistry

OBJECTIVETo evaluate the antimicrobial activities of silver inorganic materials, including silver zeolite (AgZ), silver zirconium phosphate silicate (AgZrPSi) and silver zirconium phosphate (AgZrP), against oral microorganisms. In line with this objective, the morphology and structure of each type of silver based powders were also investigated.

METHODSThe antimicrobial activities of AgZ, AgZrPSi and AgZrP were tested against Streptococcus mutans, Lactobacillus casei, Candida albicans and Staphylococcus aureus using disk diffusion assay as a screening test. The minimum inhibitory concentration (MIC) and minimum lethal concentration (MLC) were determined using the modified membrane method. Scanning electron microscope and X-ray diffraction were used to investigate the morphology and structure of these silver materials.

RESULTSAll forms of silver inorganic materials could inhibit the growth of all test microorganisms. The MIC of AgZ, AgZrPSi and AgZrP was 10.0 g/L whereas MLC ranged between 10.0-60.0 g/L. In terms of morphology and structure, AgZrPSi and AgZrP had smaller sized particles (1.5-3.0 µm) and more uniformly shaped than AgZ.

CONCLUSIONSSilver inorganic materials in the form of AgZ, AgZrPSi and AgZrP had antimicrobial effects against all test oral microorganisms and those activities may be influenced by the crystal structure of carriers. These results suggest that these silver materials may be useful metals applied to oral hygiene products to provide antimicrobial activity against oral infection.

Anti-Infective Agents ; pharmacology ; Bacteria ; drug effects ; Candida albicans ; drug effects ; Microbial Sensitivity Tests ; Powders ; pharmacology ; Silver Compounds ; pharmacology

BACKGROUND: Skin contact with, and the breathing in of air containing silver compounds can occur in the workplace. Occupational exposure to silver and its compounds is mainly via airborne dust, metal fumes, and mists of solutions containing silver compounds. Argyria results from increased serum silver levels and the deposition of silver-containing particles in the dermis and mucous membranes. The author reports a patient with generalized argyria, who worked on the manufacture of cellular phone cases. CASE REPORT: The patient was a 30 year-old male, with extensive blue-gray discoloration of the whole body, especially sun-exposed area, of 3 years duration. He had been exposed to silver in the processing of EMI for the past 4 years and gaskets for 1 year. EMI is the process by which the internal electromagnetic wave in cellular phone cases are shielded, and gaskets play an important role in shielding the electric clashes between electronic circuits, as well as increasing the durability of cellular phone cases to impact. EMI had been processed manually but this was changed to automatic spraying by robots in 2003. On physical examination, the patient had diffuse blue-gray discoloration of the skin, which was most prominent in the sun-exposed areas of his face, neck and V of the chest. Histopathological examination of a punch biopsy specimen from the posterior neck revealed fine, minute, round, and brown-black granules deposited in the basement membrane zone surrounding the eccrine glands. The laboratory findings were positive for hepatitis B antigen, with a serum silver concentration of 150.3 ppb. From this evidence, he was diagnosed with argyria due to silver exposure. DISCUSSION: The author reports a case of occupational systemic argyria due to inhalation exposure of silver compounds.
Adult ; Argyria* ; Basement Membrane ; Biopsy ; Cellular Phone* ; Dermis ; Dust ; Eccrine Glands ; Electromagnetic Radiation ; Hepatitis B ; Humans ; Hyperpigmentation ; Inhalation Exposure ; Male ; Mucous Membrane ; Neck ; Occupational Exposure ; Physical Examination ; Respiration ; Silver Compounds ; Silver* ; Skin ; Thorax

OBJECTIVETo develop antibacterial coatings for orthopedic implants with a sustained release of drugs.

METHODSWollastonite coatings were deposited on the titanium substrates by an atmospheric plasma spray system. After soaking in weight percent of 5% AgNO(3) solution for 24 h, the wollastonite coatings loading silver were obtained. Gentamicin were loaded on the wollastonite coatings by collagen grafting process. The release rates of drugs from wollastonite coatings were investigated by the in vitro solution soaking test. One strain of S. aureus was used in zone of inhibition test to evaluate the antibacterial properties of drug loaded wollastonite coatings, and the cell culture test was used to evaluate their cytotoxicity.

RESULTSSilver and gentamicin loaded wollastonite coatings were successfully prepared. The release of silver ions from the silver loaded wollastonite coatings lasted 50 d in deionized water, effectively inhibiting the growth of S. aureus for 40 d. While an initial burst release of gentamicin was found during the in vitro solution soaking test. The gentamicin released from gentamicin loaded wollastonite coatings can inhibit the growth of S. aureus for 18 d. Both the two kinds of antibacterial wollastonite coatings showed no adverse effect on cellular adhesion, proliferation and alkaline phosphatase expression.

CONCLUSIONSCompared with gentamicin loaded wollastonite coatings, silver loaded wollastonite coatings may have more promising clinical applications due to the even and long-time antibacterial agent release.

Anti-Bacterial Agents ; pharmacology ; Calcium Compounds ; Cells, Cultured ; Coated Materials, Biocompatible ; pharmacology ; Gentamicins ; pharmacology ; Materials Testing ; Microbial Sensitivity Tests ; Osteoblasts ; cytology ; drug effects ; Silicates ; Silver ; pharmacology

New silver-containing dressings developed in recent years have brought new and powerful means for the prevention and treatment of wound infection, which promote development and progress of wound therapy. There are many kinds of silver-containing dressings, however, misunderstanding and even misapplication exist in how to choose and use these dressings. Based on literature evidence, we propose this national expert consensus on clinical application of silver-containing dressings, particularly in terms of kinds and mechanisms, indications, contraindications, rational selections in different wounds, and cautions in the clinical application of silver-containing dressings. This consensus would be helpful for medical and nursing personnel to use silver-containing dressings in wound repair field in clinic correctly and professionally.
Administration, Topical ; Bandages ; Burns ; therapy ; Consensus ; Humans ; Silver Compounds ; therapeutic use ; Surgical Wound Infection ; prevention & control ; Wound Healing ; drug effects ; Wound Infection ; prevention & control ; therapy

New silver-containing dressings developed in recent years have brought new and powerful means for the prevention and treatment of wound infection, which promote development and progress of wound therapy. There are many kinds of silver-containing dressings, however, misunderstanding and even misapplication exist in how to choose and use these dressings. Based on literature evidence, we propose this national expert consensus on clinical application of silver-containing dressings, particularly in terms of kinds and mechanisms, indications, contraindications, rational selections in different wounds, and cautions in the clinical application of silver-containing dressings. This consensus would be helpful for medical and nursing personnels to use silver-containing dressings in wound repair field in clinic correctly and professionally.
Administration, Topical ; Bandages ; Burns ; therapy ; Consensus ; Humans ; Silver Compounds ; administration & dosage ; therapeutic use ; Surgical Wound Infection ; prevention & control ; Wound Infection ; therapy